1. Field of the Invention
The present invention relates to a backplane for attaching storage devices, and more particularly to a distributed, scalable backplane for attaching storage devices that utilize removable media.
2. Background of the Invention
In scalable disk array systems, a backplane is used to attach many disk drives together. This backplane serves as a means for distributing power, data, and controls to each disk drive. This prior art backplane is a single physical device throughout which all of the power, data, and controls are distributed. The backplane is typically a single motherboard which is physically similar to a wall, where the disk drives are attached to one side of the wall. This physical arrangement is possible because disk drives need access to only one side of the backplane in order to be installed in and removed from the backplane. All power, data, and controls are routed to each drive using the single motherboard backplane.
FIG. 1 is a block diagram of disk drives attached to a single motherboard backplane in accordance with the prior art. Backplane 10 is a single motherboard backplane to which disk drives 12, 14, and 16 are attached. A front 18 of the disk drives is accessible. However, when attached to backplane 10, the back 20 of the disk drives is no longer accessible.
Further, as is depicted, backplane 10 is not scalable. Backplane 10 can accommodate only a particular number of drives. Additional disk drives may not be attached to backplane 10 once this particular number is attached.
Removable media storage devices, unlike disk drives, require access to both the front and back of the devices. For example, a tape automation system includes an array of tape drives that each have removable tape cartridges. In a tape automation system, a robot must have access to a front of the tape drives in order to insert and remove the tape cartridges. The back of the tape drives must also remain accessible to service personnel who need full access to the I/O side of the drive. In addition, airflow must be permitted to travel from the front of a tape drive to the back of the drive.
Therefore, a single motherboard backplane is not practical for removable media drive array systems. A single motherboard backplane would block access to the slot for inserting and removing media.
A backplane is disclosed for attaching storage devices to the backplane that utilize removable media. The backplane is distributed and scalable. The backplane is divided into separate generally horizontal portions that each support a row of removable media storage devices. Each generally horizontal portion includes a bus for distributing electronic signals to the storage devices that are coupled to that generally horizontal portion. Each generally horizontal portion includes multiple connectors coupled to the generally horizontal portion for receiving the storage devices. The storage devices are not coupled to the backplane utilizing a front or a back of any one of the storage devices such that the front and back of each storage device remain accessible when the storage devices are coupled to the backplane.
The above as well as additional objectives, features, and advantages of the present invention will become apparent in the following detailed written description.